“Do you speak about your daddy? It’s very important to talk about it. Very, very important.”

He also told children at the Centre that he felt very angry when his mother died, and stressed again how important it is for them to talk about it. “Sometimes it hurts but we can remember the happy things too. It is so important to talk.”

Prince William is the royal patron of the Child Bereavement U.K. Centre, a charity that helps families deal with loss. It was founded by one of Princess Diana’s closest friends .

This coming summer will mark 20 years since Princess Diana died in a car accident in Paris.